EP0128210B1 - Verfahren und vorrichtung zum synchronisieren von funküberträgern für synchronfunkausstrahlen - Google Patents

Verfahren und vorrichtung zum synchronisieren von funküberträgern für synchronfunkausstrahlen Download PDF

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Publication number
EP0128210B1
EP0128210B1 EP84900311A EP84900311A EP0128210B1 EP 0128210 B1 EP0128210 B1 EP 0128210B1 EP 84900311 A EP84900311 A EP 84900311A EP 84900311 A EP84900311 A EP 84900311A EP 0128210 B1 EP0128210 B1 EP 0128210B1
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EP
European Patent Office
Prior art keywords
frequency
radio
station
transmission
message
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP84900311A
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English (en)
French (fr)
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EP0128210A1 (de
Inventor
Dag E:Son Akerberg
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Telefonaktiebolaget LM Ericsson AB
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Telefonaktiebolaget LM Ericsson AB
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Application filed by Telefonaktiebolaget LM Ericsson AB filed Critical Telefonaktiebolaget LM Ericsson AB
Publication of EP0128210A1 publication Critical patent/EP0128210A1/de
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Publication of EP0128210B1 publication Critical patent/EP0128210B1/de
Expired legal-status Critical Current

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04H—BROADCAST COMMUNICATION
    • H04H20/00—Arrangements for broadcast or for distribution combined with broadcast
    • H04H20/65—Arrangements characterised by transmission systems for broadcast
    • H04H20/67—Common-wave systems, i.e. using separate transmitters operating on substantially the same frequency
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B3/00—Audible signalling systems; Audible personal calling systems
    • G08B3/10—Audible signalling systems; Audible personal calling systems using electric transmission; using electromagnetic transmission
    • G08B3/1008—Personal calling arrangements or devices, i.e. paging systems
    • G08B3/1016—Personal calling arrangements or devices, i.e. paging systems using wireless transmission

Definitions

  • the present invention relates to a method of synchronizing radio transmitters for synchronous radio transmission and an apparatus for carrying out a part of the method, in accordance with the preambles of the independent claims 1 and 4.
  • radio transmitters For transmitting short messages by radio, particularly messages containing personal paging calls, it is usual to use a large number of radio transmitters, each with a limited range, these transmitters being adapted for synchronous radio transmission, i.e. all of them send the same message with the same frequency.
  • the transmission is modulated with binary frequency modulation (frequency shift keying, FSK), and the transmitters are further adapted for sending the message bits simultaneously.
  • FSK frequency shift keying
  • the true carrier frequency of the transmitters may deviate from the selected frequency by 50 Hz at most.
  • the frequency stability requirement is thus high, and it has so far been met by using high- stability transmitters or by transmitting signals on a radio link for synchronizing the carrier frequency of the transmitters. Both methods result in that the installations will be expensive.
  • the separate characters In a receiver which is situated such that the transmission from two transmitters is received in it, the separate characters must arrive simultaneously, or otherwise there will be uncertainty as to when the character begins and ends. It is considered that the uncertain part of a character should not exceed 20% of the character length, and with a character rate of for example 512 bits/s applicable for the mentioned POCSAG system the uncertainty may be a maximum of 250 microseconds.
  • Radio receivers for the reception of coded personal paging calls are described, inter alia, in the patent specification SE-C-365681.
  • the synchronization takes place in each particular radio transmitter, and it is carried out progressively, so that it begins in the transmitters closest to the central station and is spread like a wave to stations farther and farther away from the central station, a common time signal transmitter being superfluous.
  • a central station 1 is included in it, as illustrated in Figure 1, the transmission of personal paging calls in an extensive area being administered by the station, from which such calls are sent out by radio to paging receivers within the range of the station and on a line to subordinate radio stations 2, which are to send out calls where the central station radio transmission cannot be comprehended.
  • the subordinate stations 2 are disposed such as to send the same call message as the central station 1, and to send it simultaneously as it is sent from the central station and on the same radio frequency, or on a frequency with a preselected offset from this frequency.
  • a substation 2 which is illustrated in Figure 2 is equipped, inter alia with a data receiver 5 for receiving a message sent on a line 6 from the central station 1.
  • the message passes a delaying circuit 7 for delaying by a time Tc, before it is fed into a memory 8, which is connected to the delaying circuit, for transmission by the station radio transmitter, this time Tc specially set for each station such that the message will be transmitted simultaneously from all stations.
  • the message is also fed via a first decoder 9 into a control means 10, which is a micro computer.
  • the station is further equipped with an aerial 11, alternately transmitting and receiving.
  • a radio receiver 12 can be connected to the aerial by a switch 13 for reception of the same message as is received in the data receiver 5.
  • the message received in the radio receiver is fed via a second decoder 14 to the mentioned control means 10.
  • the control means 10 is also connected to the delay circuit 7 by a line for transmitting the necessary correction for the delay time Tc.
  • the setting of the different radio stations on frequency is carried out consecutively, starting with the substation closest to the central station, until setting has been carried out in the most remote station.
  • the central station 1 is schematically illustrated in Figure 3, together with a plurality of the subordinate stations. All the stations are provided with the described transmitters and receivers. Some of the subordinate stations, which may be called primary stations 2:1-2:3, are placed high so that the message can be sent by radio between them over fairly long distances, while other stations, which may be called secondary stations 3:11-3:19 only need to have radio communication with an adjacent primary station.
  • primary stations 2:1-2:3 Some of the subordinate stations, which may be called primary stations 2:1-2:3, are placed high so that the message can be sent by radio between them over fairly long distances, while other stations, which may be called secondary stations 3:11-3:19 only need to have radio communication with an adjacent primary station.
  • the radio connections between the stations are denoted by full lines and the wire connections by dashed lines in Figure 3.
  • the lay of the wire connections is optional, but such that all the subordinate stations are connected to the central station 1.
  • Transmission of personal paging calls by radio from the stations is controlled by the message sent on the line from the central station 1.
  • the propagation time on the line is longest to the most remote station 3:19. If the call message is sent by radio from this station as soon as it has arrived on the line, the message may only be sent after a small delay after arrival at the station 2:3, in order that the message from there will be sent simultaneously.
  • the subordinate radio stations are all equipped with a previously-mentioned radio receiver 12 of the superheterodyne type, known per se, and here of the double superheterodyne type, i.e. as illustrated in Figure 4, with a first and a second local oscillator 22, 23, a first and second mixer 24, 25 and two intermediate frequencies.
  • the receiver 21 further contains three bandpass filters 26, 27, 28 for filtering out undesired signal frequencies, a threshold circuit 29 and a demodulator 30, from the output A of which the received signal is fed to the decoder 14 in Figure 2.
  • the second intermediate frequency of the receiver is taken from the output B after the threshold circuit 29, the signals here having the frequencyfm -f Lo1 - f L02 Hz, wheref, is the frequency of the received radio signal and f LO1 and f L02 are the frequencies of the respective local oscillators.
  • the frequency of the signal at B is to be used for synchronizing the station radio transmitter to the same frequency as that of the received signal or to a frequency deviating therefrom by a selected amount.
  • a voltage-controlled crystal oscillator VCXO for the transmission frequency is arranged in the station and is intended for controlling the frequency of the radio transmitter.
  • the oscillator will be most stable and least temperature-dependent when its control crystal is allowed to oscillate with its natural frequency, which is often lower than the intended transmission frequency.
  • the crystal oscillator 44 is regulated in the installation in question to a frequency f eI N, which is the transmission frequency divided by an integer N, selected within the limits 1 to 9.
  • the output signal of the oscillator, at C in Figure 2 is fed to an auxiliary apparatus for synchronization in Figure 6.
  • the signals of both the local oscillators 22, 23 are taken out and frequency-divided by said integer N in their individual frequency dividers 34, 35.
  • a third and a fourth mixer 36, 37 are arranged in the auxiliary apparatus 31 for mixing the heterodyned frequency of the local oscillators with the frequency of the crystal oscillator.
  • the signal On output D the signal now has the frequency; (f c - f LO1 ⁇ f LO2 ) N Hz.
  • a lowpass filter 38, 39 is put in after each mixer, and a second threshold circuit 40 immediately before the output, for filtering the output signal D. Only pure frequencies are to be found in the auxiliary apparatus 31, it being sufficient to use lowpass filters here instead of bandpass filters.
  • Comparison of the received frequency with the one generated in the station is arranged such that a number of whole periods of each frequency are counted in two coacting counters 32, with simultaneous starting.
  • the signal from the crystal oscillator 44 is fed to the radio transmitter 45 of the station, the signal frequency multiplied by N and the transmitter caused to send with the thus-obtained frequency f c or with a frequency which has a selected offset from this.
  • a switch 46 is arranged before the transmitter for closing when the transmission is to take place.
  • the frequency exceeds or falls below the intended one by 14 Hz.
  • the resolution of the frequency measurement is thus sufficient for the frequency error to be kept under 50 Hz, which is the greatest permitted frequency deviation in the example.
  • the error signal fed out from the counters 32 is fed into the memory 8, Figure 2, where it is converted to a signal for setting the crystal oscillator 44 to the intended frequency.
  • the signal fed from there with the frequency f c/ N Hz has, as mentioned, its frequency multiplied by N to become f c Hz, which is the sending frequency of the transmitter.
  • the description of synchronization to the right frequency is also applicable to radio stations where the receiver is of the superheterodyne type, thus with only one local oscillator.
  • the description is also applicable where the receiver is of the homodyne type, i.e. its intermediate frequency is zero Hz.
  • the crystal oscillator 44 has a frequency stability, which is as good as can be achieved with a control crystal in a temperature-controlled oven or with a temperature- compensated crystal.
  • the synchronization to correct transmission frequency is repeated with an hourly interval in the installation to which the embodiment has been applied, the length of interval which should be selected in other cases depends on the implementation of the oscillator and the operating conditions. The synchronization only decreases the availability of the transmitter insignificantly, since it is carried out in about 10 seconds.
  • Synchronization to the right transmission frequency is carried out immediately after a setting for synchronousness in the transmission. Both settings are contained in an order included in the message.
  • This message has the same format as a message transmitted for personal paging, but with a somewhat different content so that it is not confused with a personal paging call.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Transmitters (AREA)

Claims (4)

1. Verfahren zu vor dem Senden über eine Vielzahl von Radiostationen erfolgendem Einstellen auf synchronen Betrieb auf einem Radiokanal, der für die Radioübertragung einer Nachricht in binär kodierter Form gedacht ist, z.B. eines persönlichen Ausruf-Anrufs, der auf einer Leitung von einer Zentralstation (1) empfangen wird, wobei die Sendefrequenz eines Radiosenders, der in einer der Stationen (3:16) in Übereinklang mit oder mit einem ausgewählten Versatz von der Frequenz einer Eichübertragung oder Sendung angeordnet ist, welche durch Radio von einer zweiten Radiostation (2:2) empfangen wird, gekennzeichnet durch die Schritte:
- Senden einer Nachricht, enthaltend einen Befehl zur Einstellung der Sendefrequenz auf der Leitung von derzentraistation (1) zur zweiten Station und der Station, deren Frequenz eingestellt werden soll, sowie Empfangen der Nachricht in der zweiten Station sowie in der Station, deren Frequenz eingestellt werden soll,
- Senden der empfangenen Nachricht durch Radio von der zweiten Station (2:2),
- Empfangen des gesendeten Radiosignals in einem Empfänger in der Station (3:16), deren Frequenz eingestellt werden soll,
- Vergleichen der Frequenzen der empfangenen Radiosendung mit der Schwingung, welche lokal durch einen steuerbaren Oszillator (44) erzeugt wurde, in der Station, deren Frequenz eingestellt werden soll (3:16), sowie im Falle eines Mangels an Übereinklang Einstellen des steuerbaren Oszillators (44) in Übereinstimmung mit der Frequenz.
2. Verfahren nach Anspruch 1, gekennzeichnet durch die Schritte:
in der Station, deren Frequenz eingestellt werden soll, Zählen und Vergleichen der Perioden des End-Zwischen-Frequenzsignals eines Superheterodyntypempfängers auf der einen Seite und der Perioden der Frequenz (feiN) des steuerbaren Oszillators auf der anderen Seite, welche die gedachte Sendefrequenz ist, geteilt durch eine ganze Zahl (N), gemischt mit der lokalen Empfängeroszillatorfrequenz, welche ebenso durch die ganze Zahl (N) geteilt ist.
3. Verfahren nach Anspruch 1, gekennzeichnet durch das aufeinanderfolgende Einstellen der Radiostationen von der einen, welche der Zentralstation (1 ) am nächsten ist, bis zu derjenigen, welche hiervon am weitesten entfernt ist.
4. Vorrichtung zur Durchführung des Verfahrens nach Anspruch 1, um die Sendefrequenz einer Radiostation, die in einer ersten von einer Vielzahl von Stationen (3:16) angeordnet ist, in Übereinklang mit oder mit einem ausgewählten Versatz von der Frequenz einer Eichungsübertragung oder Sendung, die durch das Radio von einer zweiten Radiostation (2:2) empfangen wird, und zum Vergleichen der Eichübertragungs- oder Sendefrequenz (fm) mit der Sendefrequenz (fc) der ersten Station (3:16), deren Empfänger vom Doppelsuperheterodyntyp ist und einem ersten und zweiten lokalen Oszillator (22, 23) versehen ist, sowie eine erste und zweite Zwischenfrequenz aufweist, gekennzeichnet durch eine Hilfseinrichtung zum Synchronisieren (31), welche mit zwei Teilerschaltungen (34, 35) ausgerüstet ist, um die Frequenz eines Signales, welches von jedem der örtlichen Oszillatoren (22, 23) in dem Empfänger (12) übernommen wird, durch eine ganze Zahl (N), und mit zwei Mischern (36, 37) zum Mischen des Signals, welches aus der Teilerschaltung herausgeführt ist, mit einem Signal, welches eine Frequenz aufweist, die die Sendefrequenz geteilt durch die gleiche ganze Zahl (N) ist und durch einen Zähler (32) zum Zählen der Anzahl der Perioden während einer ausgewählten Zeit der zweiten Zwischenfrequenz und der heterodynen Sendefrequenz sowie Ausgeben der Differenz der Anzahl der Perioden, welche während der Zählung erhalten wurden.
EP84900311A 1982-12-09 1983-12-07 Verfahren und vorrichtung zum synchronisieren von funküberträgern für synchronfunkausstrahlen Expired EP0128210B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE8207043A SE435438B (sv) 1982-12-09 1982-12-09 Forfarande for instellning av radiosendare pa samtidig sendning
SE8207043 1982-12-09

Publications (2)

Publication Number Publication Date
EP0128210A1 EP0128210A1 (de) 1984-12-19
EP0128210B1 true EP0128210B1 (de) 1986-09-17

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Family Applications (2)

Application Number Title Priority Date Filing Date
EP84900311A Expired EP0128210B1 (de) 1982-12-09 1983-12-07 Verfahren und vorrichtung zum synchronisieren von funküberträgern für synchronfunkausstrahlen
EP84900310A Expired EP0128209B1 (de) 1982-12-09 1983-12-07 Verfahren zum einstellen von funksendern für synchrone funkübertragung

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP84900310A Expired EP0128209B1 (de) 1982-12-09 1983-12-07 Verfahren zum einstellen von funksendern für synchrone funkübertragung

Country Status (8)

Country Link
US (2) US4709401A (de)
EP (2) EP0128210B1 (de)
JP (2) JPS60500040A (de)
AU (2) AU2411484A (de)
DE (2) DE3367056D1 (de)
FI (2) FI74171C (de)
SE (2) SE435438B (de)
WO (2) WO1984002437A1 (de)

Families Citing this family (34)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI71452C (fi) * 1985-04-10 1986-12-19 Arvo Mustonen Synkroniseringsfoerfarande foer ett lokalt t ex riksomfattandepersonsoekarnaets radiosaendare
CH663126A5 (de) * 1985-04-19 1987-11-13 Koechler Erika Fa Verfahren zur synchronisation mehrerer taktgesteuerter sender-empfaenger.
GB2183969B (en) * 1985-11-28 1989-10-04 Stc Plc Network equalisation
US5144412A (en) * 1987-02-19 1992-09-01 Olin Corporation Process for manufacturing plastic pin grid arrays and the product produced thereby
US4805196A (en) * 1987-04-29 1989-02-14 Gte Laboratories Incorporated Line delay compensation for digital transmission systems utilizing low power line drivers
US4850032A (en) * 1987-11-18 1989-07-18 Motorola, Inc. Simulcast data communications system
JP2615753B2 (ja) * 1988-02-10 1997-06-04 日本電気株式会社 自動位相調整方式
CA1325459C (en) * 1988-03-07 1993-12-21 Ivor R. Axford Multiple heart rate monitoring system
JPH02195737A (ja) * 1989-01-24 1990-08-02 Fujitsu Ltd 加入者無線システムの加入者局
US5065450A (en) * 1989-03-21 1991-11-12 Tft, Inc. Frequency modulated radio frequency broadcast network employing a synchronous frequency modulated booster system
US5046124A (en) * 1989-03-21 1991-09-03 Tft, Inc. Frequency modulated radio frequency broadcast network employing a synchronous frequency modulated booster system
FR2646302B1 (fr) * 1989-04-25 1993-01-15 Matra Communication Procede de pseudo-synchronisation d'un reseau de communication a multiplexage dans le temps et applications
US5054113A (en) * 1989-12-04 1991-10-01 Motorola, Inc. Communication system with bit sampling method in portable receiver for simulcast communication
US5155746A (en) * 1990-01-08 1992-10-13 Reliance Comm/Tec Corporation Clock synchronization scheme for digital transmission
US5014344A (en) * 1990-03-19 1991-05-07 Motorola, Inc. Method for synchronizing the transmissions in a simulcast transmission system
US5239671A (en) * 1990-11-13 1993-08-24 Pagemart, Inc. Simulcast satellite paging system with provision for signal interruption
US5127101A (en) * 1991-02-01 1992-06-30 Ericsson Ge Mobile Communications Inc. Simulcast auto alignment system
US5291518A (en) * 1991-09-06 1994-03-01 Metriplex, Inc. Link system for radio paging service
US5257404A (en) * 1991-10-04 1993-10-26 Motorola, Inc. Simulcast synchronization and equalization system and method therefor
US5261118A (en) * 1991-10-04 1993-11-09 Motorola, Inc. Simulcast synchronization and equalization system and method therefor
US5280629A (en) * 1991-12-06 1994-01-18 Motorola, Inc. Technique for measuring channel delay
DE69329209T2 (de) 1992-01-10 2001-04-05 Nec Corp., Tokio/Tokyo Synchronfunkrufsystem
CA2091962A1 (en) * 1992-03-31 1993-10-01 Mark L. Witsaman Clock synchronization system
US5365569A (en) * 1992-08-17 1994-11-15 Glenayre Electronics, Ltd. Digital simulcast transmission system
US5369682A (en) * 1992-08-17 1994-11-29 Glenayre Electronics, Inc. Digital simulcast transmission system
US5423059A (en) * 1993-07-29 1995-06-06 Motorola Inc. Method for enhancing signal quality in a simulcast communication system
US5481258A (en) * 1993-08-11 1996-01-02 Glenayre Electronics, Inc. Method and apparatus for coordinating clocks in a simulcast network
ATE168793T1 (de) * 1994-09-24 1998-08-15 Ebauchesfabrik Eta Ag Zeitmessung in einem kommunikationssystem, kommunikationssystem und empfänger dafür
EP0851608A1 (de) * 1996-12-31 1998-07-01 TELEFONAKTIEBOLAGET L M ERICSSON (publ) Übertragungszeitverzögerungsmessung bei Übertragungswegen in einem Funk-Telekommunikationssystem
US5873044A (en) * 1997-02-21 1999-02-16 Motorola, Inc. Method and apparatus in a radio communication system for synchronizing transmissions while maintaining full user traffic
DE10060288A1 (de) * 2000-12-05 2002-06-13 Bosch Gmbh Robert Fahrzeug mit wenigstens einem SEnsor zur Detektion des Fahrzeugumfelds
GB2415860B (en) * 2004-06-30 2007-04-18 Nokia Corp A method of providing a radio service at a remote terminal
US8543138B2 (en) * 2005-03-04 2013-09-24 Qualcomm Incorporated Multi-sector broadcast paging channel
US8174364B2 (en) * 2008-10-17 2012-05-08 Michael Kenneth Pedigo Automatic means to trigger RFID transmitters

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE820911C (de) * 1949-08-03 1951-11-15 Lorenz A G C Verfahren zum Synchronisieren von Gleichwellensendern
DD117574A1 (de) * 1974-12-19 1976-01-12
JPS5197316A (en) * 1975-02-24 1976-08-26 Eiseitsushinniokeru shuhasudokihoshiki
US4117405A (en) * 1976-11-02 1978-09-26 Louis Martinez Narrow-band radio communication system
US4255814A (en) * 1977-07-15 1981-03-10 Motorola, Inc. Simulcast transmission system
US4188582A (en) * 1978-04-10 1980-02-12 Motorola, Inc. Simulcast transmission system having phase-locked remote transmitters
US4208630A (en) * 1978-10-19 1980-06-17 Altran Electronics, Inc. Narrow band paging or control radio system
DE3020176A1 (de) * 1980-05-28 1981-12-03 Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt Verfahren und anordnung zum zeitgleichen aussenden von nachrichten ueber mehrere gleichwellensender
DE3035759A1 (de) * 1980-09-22 1982-05-13 Siemens AG, 1000 Berlin und 8000 München Verfahren und schaltungsanordnung zum ausgleichen von laufzeitunterschieden bei der uebertragung von signalen zu gleichwellen-funksendern
DE3035679A1 (de) * 1980-09-22 1982-05-06 Siemens AG, 1000 Berlin und 8000 München Verfahren und schaltungsanordnung zum einstellen der zeitpunkte des aussendens von signalen von gleichwellen-funksendern, insbesondere einer fahrzeugverkehrsleitanlage
US4411007A (en) * 1981-04-29 1983-10-18 The Manitoba Telephone System Distributed network synchronization system
US4578815A (en) * 1983-12-07 1986-03-25 Motorola, Inc. Wide area coverage radio communication system and method

Also Published As

Publication number Publication date
SE8400169L (sv) 1984-01-13
WO1984002437A1 (en) 1984-06-21
SE435438B (sv) 1984-09-24
AU2411584A (en) 1984-07-05
DE3366347D1 (en) 1986-10-23
WO1984002436A1 (en) 1984-06-21
FI843120A0 (fi) 1984-08-08
JPH0423968B2 (de) 1992-04-23
FI74172B (fi) 1987-08-31
FI74171B (fi) 1987-08-31
US4709402A (en) 1987-11-24
FI843119A (fi) 1984-08-08
FI74171C (sv) 1987-12-10
EP0128210A1 (de) 1984-12-19
FI74172C (sv) 1987-12-10
EP0128209B1 (de) 1986-10-15
DE3367056D1 (en) 1986-11-20
AU2411484A (en) 1984-07-05
US4709401A (en) 1987-11-24
JPS60500158A (ja) 1985-01-31
SE456294B (sv) 1988-09-19
FI843120A (fi) 1984-08-08
SE8207043D0 (sv) 1982-12-09
FI843119A0 (fi) 1984-08-08
SE8207043L (sv) 1984-06-10
EP0128209A1 (de) 1984-12-19
SE8400169D0 (sv) 1984-01-13
JPS60500040A (ja) 1985-01-10

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